Isoprene (2-methyl-1,3-butadiene) is an important organic compound used in a wide array of applications. For instance, isoprene is employed as an intermediate or a starting material in the synthesis of numerous chemical compositions and polymers. Isoprene is also an important biological material that is synthesized naturally by many plants and animals, including humans.
The isoprene used in industrial applications is typically produced as a by-product of the thermal cracking of petroleum or naphtha or is otherwise extracted from petrochemical streams. This is a relatively expensive, energy-intensive process. With the worldwide demand for petrochemical based products constantly increasing, the cost of isoprene is expected to rise to much higher levels in the long-term and its availability is limited in any case. There is concern that future supplies of isoprene from petrochemical-based sources will be inadequate to meet projected needs and that prices will rise to unprecedented levels. Accordingly, there is a need to procure a source of isoprene from a low cost, renewable source which is environmentally friendly.
Several recent advancements have been made in the production of isoprene from renewable sources (see, for example, International Patent Application Publication No. WO 2009/076676 A2). Such methods produce isoprene at rates, titers, and purity that may be sufficient to meet the demands of a robust commercial process, however process improvements to reduce the operational costs associated with the production of isoprene derived from biological sources, and to increase yields of isoprene are needed.
All patents, patent applications, publications, documents, nucleotide and protein sequence database accession numbers, the sequences to which they refer, and articles cited herein are all incorporated herein by reference in their entireties.